/**
 *    Copyright ${license.git.copyrightYears} the original author or authors.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package org.mybatis.generator.plugins;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.mybatis.generator.api.FullyQualifiedTable;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.IntrospectedTable.TargetRuntime;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.FullyQualifiedJavaType;
import org.mybatis.generator.api.dom.java.Interface;
import org.mybatis.generator.api.dom.java.Method;
import org.mybatis.generator.api.dom.java.Parameter;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.Document;
import org.mybatis.generator.api.dom.xml.XmlElement;

/**
 * This plugin will add selectByExample methods that include rowBounds parameters to the generated mapper interface.
 * This plugin is only valid for MyBatis3.
 * 
 * @author Jeff Butler
 */
public class RowBoundsPlugin extends PluginAdapter {

  private FullyQualifiedJavaType rowBounds;
  private Map<FullyQualifiedTable, List<XmlElement>> elementsToAdd;

  public RowBoundsPlugin() {
    rowBounds = new FullyQualifiedJavaType("org.apache.ibatis.session.RowBounds"); //$NON-NLS-1$
    elementsToAdd = new HashMap<FullyQualifiedTable, List<XmlElement>>();
  }

  public boolean validate(List<String> warnings) {
    return true;
  }

  @Override
  public boolean clientSelectByExampleWithBLOBsMethodGenerated(Method method, Interface interfaze,
      IntrospectedTable introspectedTable) {
    if (introspectedTable.getTargetRuntime() == TargetRuntime.MYBATIS3) {
      copyAndAddMethod(method, interfaze);
    }
    return true;
  }

  @Override
  public boolean clientSelectByExampleWithoutBLOBsMethodGenerated(Method method, Interface interfaze,
      IntrospectedTable introspectedTable) {
    if (introspectedTable.getTargetRuntime() == TargetRuntime.MYBATIS3) {
      copyAndAddMethod(method, interfaze);
    }
    return true;
  }

  @Override
  public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element,
      IntrospectedTable introspectedTable) {
    if (introspectedTable.getTargetRuntime() == TargetRuntime.MYBATIS3) {
      copyAndSaveElement(element, introspectedTable.getFullyQualifiedTable());
    }
    return true;
  }

  @Override
  public boolean sqlMapSelectByExampleWithBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
    if (introspectedTable.getTargetRuntime() == TargetRuntime.MYBATIS3) {
      copyAndSaveElement(element, introspectedTable.getFullyQualifiedTable());
    }
    return true;
  }

  /**
   * We'll override this method and add any new elements generated by previous calls
   */
  @Override
  public boolean sqlMapDocumentGenerated(Document document, IntrospectedTable introspectedTable) {
    List<XmlElement> elements = elementsToAdd.get(introspectedTable.getFullyQualifiedTable());
    if (elements != null) {
      for (XmlElement element : elements) {
        document.getRootElement().addElement(element);
      }
    }

    return true;
  }

  /**
   * Use the method copy constructor to create a new method, then add the rowBounds parameter.
   * 
   * @param fullyQualifiedTable
   * @param method
   */
  private void copyAndAddMethod(Method method, Interface interfaze) {
    Method newMethod = new Method(method);
    newMethod.setName(method.getName() + "WithRowbounds"); //$NON-NLS-1$
    newMethod.addParameter(new Parameter(rowBounds, "rowBounds")); //$NON-NLS-1$
    interfaze.addMethod(newMethod);
    interfaze.addImportedType(rowBounds);
  }

  /**
   * Use the method copy constructor to create a new element
   * 
   * @param fullyQualifiedTable
   * @param method
   */
  private void copyAndSaveElement(XmlElement element, FullyQualifiedTable fqt) {
    XmlElement newElement = new XmlElement(element);

    // remove old id attribute and add a new one with the new name
    for (Iterator<Attribute> iterator = newElement.getAttributes().iterator(); iterator.hasNext();) {
      Attribute attribute = iterator.next();
      if ("id".equals(attribute.getName())) { //$NON-NLS-1$
        iterator.remove();
        Attribute newAttribute = new Attribute("id", attribute.getValue() + "WithRowbounds"); //$NON-NLS-1$ //$NON-NLS-2$
        newElement.addAttribute(newAttribute);
        break;
      }
    }

    // save the new element locally. We'll add it to the document
    // later
    List<XmlElement> elements = elementsToAdd.get(fqt);
    if (elements == null) {
      elements = new ArrayList<XmlElement>();
      elementsToAdd.put(fqt, elements);
    }
    elements.add(newElement);
  }
}
